Re: [Matplotlib-users] Using labels with "twinx()"

[Stephen G. <ste...@op...>]

On 28/09/2011 4:32 PM, Klonuo Umom wrote:
> Please consider:
>
>     plot([1, 2, 3, 4], label='line 1')
>     twinx()
>     plot([11, 12, 11, 14], label='line 2')
>     legend()
>
>
> will draw only label for 'line 2'
>
>     plot([1, 2, 3, 4], label='line 1')
>     legend()
>     twinx()
>     plot([11, 12, 11, 14], label='line 2')
>     legend()
>
>
> same result, as it will overwrite label 'line 1' with label 'line 2'
>
> How to deal with this, without manually positioning legends and if 
> possible including all annotated plot lines in one legend?
>
>
> Thanks
>

I would do something like

    from matplotlib import pylab

    LegendText = []

    pylab.twinx() # << had to move before first plot else it blew up

    pylab.plot([1, 2, 3, 4] )
    LegendText.append('line 1')

    pylab.plot([11, 12, 11, 14])
    LegendText.append('line 2')

    pylab.legend( LegendText , loc='lower right')

    pylab.show()


Don't know if there is a better way
Steve